Propofol infusion in children.
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Anesthetics, Intravenous↗
Biomedical subjects
R Bray
Publications and source records attributed to R Bray.
Conservative lower back treatment reduces inhibition in knee-extensor muscles: a randomized controlled trial.
BACKGROUND: Knee-joint pathologies, such as anterior knee pain (AKP), are associated with strength deficits and reduced activation of the knee extensors, which is referred to as muscle inhibition (MI). MI is thought to prevent full functional recovery, and treatment modalities that help to reduce or eliminate MI appear necessary for successful rehabilitation. Clinical observations suggest that AKP is typically associated with sacroiliac (SI) joint dysfunction. It is unknown whether SI-joint dysfunction contributes to knee-extensor deficits and whether correction of SI-joint dysfunction alleviates MI. OBJECTIVE: The objective of this study was to assess whether conservative low back treatment reduces lower limb MI. STUDY DESIGN: In a randomized, controlled, double-blind study the effects of conservative lower back treatment on knee-extensor strength and MI were evaluated in patients with AKP. METHODS: Twenty-eight patients with AKP were randomly assigned to either a treatment or a control group. After a lower back functional assessment, the treatment group received a conservative treatment in the form of a chiropractic spinal manipulation aimed at correcting SI-joint dysfunction. The control group underwent a lower back functional assessment but received no joint manipulation. Before and after the manipulation or the lower back functional assessment, knee-extensor moments, MI, and muscle activation during full effort, isometric knee extensions were measured. RESULTS: Patients showed substantial MI in both legs. Functional assessment revealed SI-joint dysfunction in all subjects (23 symptomatic and 5 asymptomatic). After the SI-joint manipulation, a significant decrease in MI of 7.5% was observed in the involved legs of the treatment group. MI did not change in the contralateral legs of the treatment group or the involved and contralateral legs of the control group. There were no statistically significant changes in knee-extensor moments and muscle activation in either group. CONCLUSIONS: The results of this study suggest that SI-joint manipulation reduces knee-extensor MI. Spinal manipulation may possibly be an effective treatment of MI in the lower limb musculature.
Adult↗
Kind strangers? Physicians through the eyes of Tennessee Williams.
In Louisiana, Tennessee Williams is usually thought of as a famous denizen of the French Quarter or perhaps as our greatest playwright. Medicine rarely enters into it. Illness, however, particularly mental illness, shaped much of Williams' life and his work. The playwright had mixed feelings about physicians and their effect on his life and that of his close relations. These feelings worked their way into his plays. Through it all Williams gives a vivid, humorous, and deeply truthful image of the doctor-patient relationship in the first half of the twentieth century. Here we give a brief review of medicine in Williams' work.
Attitude to Health↗
Spinal imaging and intervention: 1998.
Imaging of the lumbar spine is the most common application of magnetic resonance (MR) imaging in many radiologic practices. MR imaging has replaced computed tomography (CT) and CT myelography as the primary mode of spinal imaging and has relegated myelography to a secondary role in the evaluation of lumbar spinal disorders. At the same time, however, it has become evident that the correlation between gross anatomic findings as depicted on MR images and the clinical signs and symptoms detected by the clinician may be lacking. Defining the precise anatomic source of patients' complaints on the basis of imaging studies must be approached judiciously because a significant proportion of the population has disc disease as depicted on imaging studies, yet many have no clinical findings.
Disease Progression↗
U.S.-Canadian Consensus recommendations on the immunophenotypic analysis of hematologic neoplasia by flow cytometry: data analysis and interpretation.
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Antigens, Neoplasm↗
In vivo comparison of scanning technique and wavelength in laser Doppler perfusion imaging: measurement in knee ligaments of adult rabbits.
At present, there are only two laser Doppler perfusion imaging systems (LDIs) manufactured for medical applications: a 'stepwise' and a 'continuous' scanning LDI. The stepwise scanning LDI has previously been investigated and compared with coloured microsphere determined standardised flow. The continuous scanning LDI is investigated and compared with the stepwise scanning LDI for its ability to measure in vivo, hypoaemic, ligament tissue blood flow changes. The continuous scanning system was supplied with two lasers, red and near infrared (NIR), allowing for additional assessment of the effect of wavelength on imaging ligament perfusion. Perfusion images were obtained from surgically exposed rabbit medial collateral ligaments (MCL). Continuous and stepwise LDI scans were compared using correlation and linear regression analysis of image. averages and standard deviations. Using the same method of analysis, LDI measurements using red and NIR lasers indicated a high degree of correlation, at least over the ranges of perfusion assessed, indicating that red and NIR lasers measure similar regions of flow in the rabbit MCL. These experiments confirm that both LDI techniques provide a valid in vivo measure of dynamic changes in connective tissue perfusion and could have significant impact on the understanding and treatment of joint injury and arthritis.
Animals↗
Evaluation of laser Doppler imaging to measure blood flow in knee ligaments of adult rabbits.
Laser Doppler imaging (LDI) is investigated as a novel method for in vivo ligament tissue blood flow determination. LDI output signal is obtained from surgically exposed rabbit medial collateral ligaments (MCL). The LDI signal is compared with simultaneously determined, coloured microsphere (CM)-derived standardised MCL blood flow. Correlation of LDI output with the CM flow data and a linear regression of 17 data points in nine rabbits (joint injured to provoke an acute vascular response in the tissues) indicate that LDI provides a reasonable estimate of MCL blood flow, at least over the ranges assessed. If properly calibrated, and given enough tissue-specific data points, LDI may have advantages over conventional, but more invasive, techniques. The potential clinical application of LDI technology to joint injury and arthritis research is discussed.
Animals↗
DNA index and ploidy distinguish normal human parathyroids from parathyroid adenomas and primary hyperplastic parathyroids.
BACKGROUND: The goal of this study was to identify factors that might aid in diagnosis and intraoperative management of hyperparathyroidism. METHODS: We analyzed biopsy specimens of 242 parathyroids from 159 patients by use of flow cytometry and image cytometry (ICM) for DNA index (DI), defined as the content of nuclear DNA compared with that expected for a DNA diploid standard, for proliferative index (PI), and for ploidy (diploid versus aneuploid or tetraploid). RESULTS: True normal and normal parathyroids from patients with solitary adenomas were uniformly diploid. Abnormal ploidy (aneuploidy or tetraploidy) was identified frequently in adenomas and occasionally in hyperplasias with the exception that multiple endocrine neoplasia (MEN) biopsy specimens were uniformly diploid. DI for adenomas was similar to that for hyperplasias, and DI of both was higher than for normal glands. ICM-DI correlated positively with flow cytometry-DI and patient age and inversely with serum parathyroid hormone. PI was relatively low in all groups but was higher for hyperplasias versus normal parathyroids from patients with solitary adenomas and MEN versus non-MEN. PI correlated inversely with patient age. CONCLUSIONS: DI by ICM differentiates normal from abnormal parathyroids. DI might influence extent of resection in two- and three-gland hyperplasia and selection of the most appropriate gland for autografting and cryopreservation in patients with four-gland hyperplasia.
Adenoma↗
Abnormality of the contralateral ligament after injuries of the medial collateral ligament. An experimental study in rabbits.
The right medial collateral ligament of ninety-four adult, female rabbits was transected operatively. At three, six, fourteen, or forty weeks after the operation, the uninjured, contralateral (left) medial collateral ligaments of seventy-eight of the animals were tested biomechanically and compared with the left medial collateral ligaments of thirty-three normal female rabbits. The diameters of the mid-substance collagen fibrils in the medial collateral ligaments were also measured in the uninjured, contralateral hindlimbs of four animals at each interval and compared with the fibril diameters in three normal animals at each of three corresponding intervals. Subtle but significant differences between the uninjured, contralateral and the normal medial collateral ligaments with regard to biomechanical properties of collagen fibril diameters were found at all time-intervals. These results support the notion of a significant effect on the contralateral ligament after an injury to the medial collateral ligament and suggest that contralateral ligaments cannot be considered as a normal control group even in this relatively benign model of knee injury.
Analysis of Variance↗
No effect of mop-ending on ligament healing. Rabbit studies of severed collateral knee ligaments.
We have tested the hypothesis that increasing the surface area of cut ligament ends by the creation of "mop-ends" may alter the mechanical properties of healing medial collateral ligaments. In one group of New Zealand white rabbits, a 4-mm midsubstance segment was removed from the right ligament creating a gap (sharp cut-end healing group). In the other group, a similar gap was created but, in addition, cut ligament ends were split longitudinally across the width of the ligament creating "mop-ends", roughly tripling the total injury surface area. In all animals, the contralateral (left) leg was not operated on and served as an internal control. At least 8 animals from each injury model were killed at 3, 6, 14, and 40 weeks post-operatively. Both histological and mechanical tests showed that sharp-cut and mop-end injuries healed at similar rates with similar material.
Animals↗
Water content alters viscoelastic behaviour of the normal adolescent rabbit medial collateral ligament.
Testing environment is an important factor in the outcome of mechanical tests on connective tissue. The purpose of this investigation was to determine the effect of ligament water content on ligament mechanical behaviour by altering the test environment. Water content of medial collateral ligament (MCLs) from 19 three-month-old New Zealand White rabbits was varied in subsets of ligaments pairs by means of immersion in 2, 10 or 25% sucrose or 0.9% phosphate-buffered saline (PBS) solutions for 1 h. One knee joint was cycled 50 times in the designated solution (experimental), while the contralateral knee (uncycled control) was simultaneously soaked in the same tank. Following cycling, the water contents of both test and control ligaments were determined. Water contents of 22 normal MCLs were determined immediately post-sacrifice and served as 'normal water content' controls. Normalized peak cyclic load changes were used as a measure of the viscoelastic behaviour of each MCL. Results demonstrated that only ligaments soaked (but not cycled) in a 10% sucrose solution had water contents (60.5 +/- 2.5%) which were statistically similar to the 22 fresh normal MCLs (63.9 +/- 6.0%). Ligaments soaked in PBS (74.0 +/- 1.3%) or 2% sucrose (69.2 +/- 2.3%) had significantly higher water contents compared to fresh normal MCLs. Ligaments with higher water contents (e.g. soaked in PBS or 2% sucrose) demonstrated greater cyclic load relaxation compared to ligaments with lower contents (e.g. soaked in 25 or 10% sucrose). Different fluid test environments can significantly alter ligament water content and, in turn, significantly affect ligament viscoelastic behaviour.
Animals↗
Necrobacillosis with pancytopenia.
Two young children whose presentation with necrobacillosis caused considerable diagnostic difficulty resulting in referral to an oncology unit are described. In both cases their severe suppurative multisystem illness was complicated by pancytopenia. One had bone marrow infarcts and severe endocarditis in addition to pulmonary involvement and the other had osteitis which resulted in a deformed humerus.
Anti-Bacterial Agents↗
Collagen fibril diameters in the healing adult rabbit medial collateral ligament.
This study was carried out to test the hypothesis that improvements in ligament scar mechanical behavior during healing may be related, in part, to increases in collagen fibril diameters. Forty-eight adult female New Zealand White rabbits had standardized midsubstance gap injuries created in their right medial collateral ligaments (MCLs) and were allowed normal cage activity until sacrifice in groups of 12 at 3, 6, 14 or 40 weeks post-injury. Eight animals in each group had both MCLs tested biomechanically while 4 animals had transmission EM investigation of midsubstance collagen fibril diameters by a standardized protocol. Results of mechanical tests showed a three- to fourfold increase in scar strength and stiffness over the intervals of healing studied while there was no change in collagen mean fibril minimum diameters. These results demonstrate no correlation between material or structural properties of scar and collagen fibril diameters in this model of healing and suggest that other mechanisms for scar mechanical improvement under these conditions must be investigated.
Animals↗
New dysmorphic syndrome with choanal atresia in siblings.
We report five children from three families who presented with bilateral choanal atresia associated with a spectrum of additional malformations including cardiac defects, deafness, defects of the external ear, eyes and eye lids and a characteristic dysmorphic appearance. The children were of normal intelligence. This syndrome is distinct from CHARGE association.
Abnormalities, Multiple↗
The effects of initial end contact on medial collateral ligament healing: a morphological and biomechanical study in a rabbit model.
In this investigation, the effect of initial end contact on medial collateral ligament (MCL) healing was studied in the rabbit model. Sixty-eight 1-year-old New Zealand white rabbits were separated into two groups. In one group, a 4 mm saggital Z-plasty was performed in the right MCL midsubstance (contact group), and in the other group, an analogous 4 mm midsubstance segment was removed (gap group). Left knees were unoperated to serve as internal contralateral MCL controls. Animals had unrestricted cage activity until sacrifice in groups of eight at 3, 6, 14, and 40 weeks postoperatively. Early results demonstrated that contact and gap injuries healed with what appeared to be scar tissue both morphologically and biomechanically. In both groups, laxities recovered to their contralateral values within 6 weeks and biomechanical viscoelastic behaviors recovered to 68-92% of contralaterals by 14-40 weeks. Despite these similarities, contacts showed morphological and biomechanical evidence of improved healing over gaps. Contact scars remodeled more quickly, recovered laxity more quickly, and were generally closer to contralaterals than gaps in terms of their structural strength, stiffness, and material behaviors, after 40 weeks of healing. With the exception of appearances and failure stress, all measured properties of contact healing MCLs were statistically indistinguishable from contralateral MCLs at 40 weeks of healing. These advantages of contact healing in this model support speculations that there are differences in the early rate and possibly in the later quality of ligament healing when cut rabbit MCL ends are in proximity. Longer-term studies to define end points and mechanisms of healing are required.
Animals↗
A quantitative analysis of matrix alignment in ligament scars: a comparison of movement versus immobilization in an immature rabbit model.
This investigation quantified the alignment of fibrillar matrix in normal rabbit medial collateral ligaments (MCLs) and in healing MCLs from animals treated with or without knee immobilization. Twenty-four immature female rabbits were given complete midsubstance injuries to their right MCLs. Fifteen of them had that knee pin immobilized in flexion, while the remaining nine were allowed unrestricted cage activity. Animals were sacrificed in groups of three at intervals of 3, 6, or 14 weeks after injury, and both healing MCLs and unoperated contralateral controls were fixed in situ for subsequent removal, freeze-fracture, and preparation for scanning electron microscopy (SEM). A random sampling of SEM photographs followed by automated, statistically validated image processing was used to quantify alignment of matrix in all samples. Results showed that nonimmobilized MCL scars in this model do remodel over 14 weeks of healing, returning to normal alignment values in that time. Surprisingly, MCL scars in immobilized knees were even better, with mean matrix alignments falling statistically within normal MCL limits at all healing intervals studied. If not due to an unknown sampling or fixation artifact, these results suggest that gross knee flexion and extension is not a prerequisite for scar matrix alignment in this immature model of ligament healing.
Animals↗
Lumbar nerve root compression and interstitial cystitis--response to decompressive surgery.
An identifiable lumbar nerve root compression appears to cause urological dysfunction consistent with interstitial cystitis. Ten patients (9 females, 1 male) were evaluated for chronic pelvic pain. Cystoscopic and histological appearances were consistent with a diagnosis of interstitial cystitis. Magnetic resonance studies of the lower spine consistently demonstrated a lateral compression of the L5 dorsal nerve root. Decompression of the lateral foramina of L5 resulted in immediate relief of pain in 9 patients, who have been followed up for 6 months without a recurrence. Possible mechanisms involving sympathetic dystrophy of the pelvic plexus are reviewed.
Cystitis↗